Improved method op removing bars from rivers and harbors



SYDNEY S. DURFEE, OF "CHICAGO, ILLINOIS, ASSIGN OR TO HIMSELF ANDCHARLES A. GREGORY, OF SAME ILAOE.

Letters Patent No. 60,864, dated January 1, 1867.

IMPROVED METHOD 0I' REMVING .BARS FROM RIVERSAND HARBORS.

Be it known that I, SYDNEY S. DURFEE, of Chicago, county oi' Cook, andState of Illinois, have invented a 'newand'improvd Mode of Removing SandBais from the beds oi' Rivers, the mouths of Ports and Harbors, andother similar places; and I do hereby declare that the following is afull andexactdescription thereof, reference being had to theaccompanying drawings, forming a part of this specification.

The nature of'my invention consists in placing obstructions or agitatorsat the bottoms of rivers, or in the entrances of ports-and harbors, andother places of like character, where there'are bars of sand or gravelto be removed-,whereby the action of the current orv uiidertow is madeto wear and wash away the bar, and thus deepen the channel. l

To enable others skilled in the art to make and use my invention, Iproceed to describe its construction and operation.

I take a chain of the proper size-and strength, that is to say,vfro'rnone-half tofthree-quarters of an inch, and long enough to extend quiteacross the bar I desire to remove, and attach to this chain at properintervals, or at about twenty feet apart, which I think near enough toeffect the purpose, a number of wooden blocks, from ifteen totwenty-four inches in height, and from ten to fifteen inches in width,and of the form represented in the drawing, Figure A, lor nearlyresembling a tunnel, suchas is in common use for pouring liquids into abottle, or of the form shown'in Figures C yD. This attachment may bemade by means of rings set at proper intervals in said chain, andinserting the necks of the blocks into the rings, where they can be thensecured by bolts or Screws, or may be made in any other suitable way. Ateach end .of the chain I attach, by way oi' anchor, a piece of iron,shaped as in the drawings, Figure Bkor very lmuch like the upper shellof a tortoise, convex above and concave below, and with a hole or hook,-or any other convenient attachment for the chain, about halt way betweenthe apex of the anchor and the edge thereof. Or the anchor may be of anyother suitable shape, so as not to be easily moved by the current, andof a sizeV and weight suihcient to keep the chain xed in one place,Onnearly so, and varying somewhat according to the length of the chain,the force of the current, and other attendantcircumstances. No exactrule as to weight can be given, but for all ordinary use I think four oriv'e hundred pounds would be sutlicient. If the chain is very long, oneor more additional anchors may be employed, if required, in the middleof the chain or at convenient intervals. For all ordinary bars, however,an anchor at each end' will'suiciently answer the purpose. The chainthus prepared, with its blocks and anchors attached, is then to be sunkacross the bar in the direction of the current at the place where ,itYis required to create a channel or 'to deepen one already existing.Other chains of equal length and prepared in the same manner are nextplaced across the bar parallel to the rst, and at a distance from eachother varying, according to circumstances, from twenty to fifty feet.The distance is not important provided the chains are near enough toeach other thoroughly to do the work. For all ordinary bars I thinkfifty eetto be the proper distance; if the bar is of a heavier and morecompact character the chains may require to bc placed alittle ncarcr.-The number of chains will, ofcourse, depend upon the width of channelrequired, but partly, also, on the height oithe bar, the force of thecurrent, and other circumstances. Iii-ordinary cases a single chain willopen a channel of about fifty feet in width at the top, and considerablyless than that at 'the bottom. Five chains, then, would open` a channelabout two hundred and lii'tyfeet at the top, which would be as wide asis usually required. Ii' tire bar is very compact and heavy, or if thecurrent or undertow is feeble, the chains would need to be nearertogether than where the bar is ylight orvthe current strong.' Noparticular rule can be given here, and none needed, since whether thechains are placed at thirty, forty, or iifty feet apart, the cl'ect willbe very much the same, only wherethey are nearer tbgether the work maybe done somewhat sooner. y

The manner in which this invention operates is as follows: Wherever abar is formed in thc bed oi'ar1.ve1, it will be found that the current,though rapid, is smooth and unbroken; hence it glides smoothly over thebar without impinging against itor cutting into it. But if, now, anyobstruction is placed in the'bed of the river, the current is at. oncebroken and deflected from its straight course. If the obstruction is ofthe right shape, and, to acci-tain extent, if oi' almost any shape, thecurrent is made to in'ipinge against the bottom, to cut into it, andnecessarily, therefore, to cut it away and wash it away. Ii'theseobstructions are placed near enough together, `and in a right line, theei'ect will be to cut a channel more or less deep as far as theobstructions extend. Thus, in the particurf lar method `described above,a channel will be cut for the whole lengthof thc chain; the sand or mudwill be cut casa: 2

into, loosened, and washed away. The chain, with its blocks attached,will contlnuallysettle lower and lower,

sandAwill be washed in towards the chain from lbeth sides and thenwashed away, until at last a suicient depth of water is obtained, whenthe chain may be taken up and'used elsewhere. In this way the currentoi' the river is made to perform the whole work of cuttingaway the bar;no dredging is required, land no other expense except the comparativelytriing cost of the chains, blocks, and anchors'. In' the mouths ofharbors the same effect is produced, but in a somewhat di'ierent way.Here, as a general rule, there is little or no current at the bottom ofthe channel. But during every storm there is a heavy undertow, whichwill perform the same service .aslthe current in the river. Thisundertow only needs to be broken up into eddics and cross-currents toeut into and washI away the bar; which it will do with a rapidityhardly. to be believed by one who has never witnessed the operation. Thesame result may be produced on bars Where no channel previously existed;.and thus new harbors may be opened Whenever there is an inner body ofwater deepI enough for shipping, with a bar across the entrance.

Theadvantages of this invention are greatand manifest. In nearly all ourharbors, both on the lakes and on the seaboard, the formation of bars inthe channel is a great, a constantly renewed, and constantly increasingevil. The expense-of removing these bars in the ordinary way, bydredging, is immense; and yet they must'be 'removed or the trade andcommerce of our lake and seaboard towns and cities will be seriouslyinjured, or even wholly lost. The same is true, though to a less extent,with many of our rivers. Any'eheap and effectual way of removing thebars by which their navigation is impeded would be a national blessing,and this way I think I have invented.

In describing my invention above it will be seen that I have confinedmyself to. one particular contrivance, viz, a chain or series of chains,with wooden blocks of a certain shape attached. I have done this, notwith any view of limiting my claim to this particular device, but simplybecause that is the form and arrangement which I deem, yon the whole,best tted to answer the intended purpose. It is obvious, however, thatmany `modifications of this plan may be adopted Without departing fromthe principle of my invention. Thus, instead of a chain,oa timber ortimbers, or even a stout rope, may be used to' support the blocks; oreach block may be kept in place by being attached to an anchor, made asabove explained; or, instead of vusing blocks of wood, and of theparticular shape shown in the drawings, other blocks, made of iron andhollow, or of any other suitable material, and of a .great variety ofshapes, may be substituted.' None of these details of construction aredeemed material. All that is essential is, ythat there should be aseries 'of obstructions or agitators fixed in the bottom of the channel,to break the current and turn it against the bar, as above explained.

What I claim, then, as my invention, and desire to secure by LettersPatent, is

The method of removing bars of sand, or mud, or gravel, in the beds ofrivers, or at the mouths of ports and harbors, or similar places, byplacing obstructions or agitators upon said bars, for the purposeof'breaking up the current, and thereby causing it to cut intoV and washaway the bar, all substantially as above shown.

In witness whereof I have hereto set my hand this 15th day of December,one thousand eight hundred and sixty-five.

SYDNEY S. DURFEE.

Witnesses Gnonen PAYsoN, OBADIAH Jackson.

